Best Practice for Connecting a Tracker to Battery Power

This is article is applicable for the TennaCANbus, TennaMINI 2.0 Plug-In Solar, TennaMINI Plug-In Solar, TennaCAM 2.0, and TennaCAM 2.0 Heavy Equipment.

Most automotive electrical systems today use lead acid batteries that provide 12V DC or 24V DC. Other voltages, such as 6V DC and 48V DC may be encountered sometimes. Higher voltages are typically found in larger/heavier vehicles (such as those commonly found in the construction industry).

12V systems are normally use a single battery, while 24V systems may have either a single battery (24V) or a combination of two 12V DC batteries connected in series.

Making direct connections to the battery posts is the best practice for continuous, reliable power.

What makes for a good connection to the battery posts?

Lead acid batteries, often found in the engine compartment, automotive batteries are expected to perform in temperature extremes, in high vibration conditions, and may sometimes be exposed to engine liquids (such as water, anti-freeze, oil, gas, and others). This environment can cause the battery terminals, if not properly protected, to become corroded or the connections to them to become loose over time. Corroded and loose connections can cause multiple performance issues for the vehicle, and these can often be hard to diagnose – as simple as they may be to address and fix.

Corrosion on the battery posts causes a layer of insulation to be built up between electrical connections. This reduces the ability of the battery post (negative or positive) to deliver proper power levels as the corrosion acts as a resistive/insulating layer.

Loose connections to a battery post (negative or positive) may cause intermittent connections, thus reducing the reliability of power available to an accessory connected to the battery. Furthermore, if the loose connection is one that is intended to provide high currents (as lead acid batteries are), arcing may occur during high load conditions. This arcing causes the deposition of carbon on the battery posts (and other components connected to it) over time, creating a resistive/insulating layer that reduces the expected performance of the battery.

A good and reliable connection to a battery is one that is made to a clean battery post and is mechanically sound. This connection must also be free of any insulators such as grease, paint, powder coating, and others. A connection between “shiny metal” pieces is always desired.

Examples of Good Connections

• A “shiny” ground connection (in a dirty environment).

• Connections to 24V battery posts neatly dressed and protected.

Examples of Bad Connections

• Corroded battery terminal.

• Chassis ground connection onto a powder coated surface.

• Chassis ground connection onto a painted surface.

• Loose and fraying connection.

Other Considerations for a Continuous Connection to a Battery

Heavy duty vehicles used in the construction industry are often fitted with master battery disconnect switches. These switches, as their name implies, are used to disconnect a vehicle’s electrical systems from the battery in order to avoid having these systems drain the battery (if the vehicle is not used over an extended period of time).

Tenna trackers are designed to not drain the asset's battery. Some Tenna trackers consume very little power when connected to the battery and ignition is off (less than a battery’s self-discharge rate), while some other Tenna trackers consume no power from the battery when the ignition is off (and rely uniquely on their built-in tracker battery for their continued operation).

Connecting Tenna trackers to the non-switched side of the master switch is important for proper tracker and Tenna operation. 12V or 24V should be available to the tracker when the master switch is engaged and also when the master switch is not engaged.

Testing a connection with a master switch (24V present for the tracker at all times).